Solubility Product
Definition and meaning of Solubility Product in chemistry.
The solubility product, commonly denoted by the symbol Ksp, is the thermodynamic equilibrium constant for a solid ionic substance actively dissolving in an aqueous solution. It represents the exact maximum level at which a solute dissolves in a given solvent to form a perfectly saturated solution.
In more detail
For any ionic compound, the Ksp is mathematically calculated by multiplying the molar concentrations of its dissolved constituent ions, with each concentration raised to the power of their respective stoichiometric coefficients from the balanced dissolution equation. A higher numerical Ksp value generally indicates a much more soluble chemical compound under standard conditions. When the mathematical product of the actual ion concentrations present in a solution exceeds the established Ksp value, the solution is considered supersaturated, and solid precipitation will inevitably occur until equilibrium is restored.
Key facts
| Field | Physical Chemistry |
|---|---|
| Formula | CaCO3 |
| Symbol | Ksp |
| Condition | Applies exclusively to saturated solutions |
The solubility product equilibrium expression for solid calcium carbonate (CaCO3) dissociating into water is simply written as Ksp = [Ca 2+][CO3 2-].
Frequently asked questions
What exactly happens if the reaction quotient Q is greater than the Ksp?
If the reaction quotient Q is numerically greater than the Ksp, the solution is temporarily supersaturated and a solid precipitate will spontaneously form until the concentration drops back to equilibrium.